Speed change system



April 1946- v R. s. TAYLOR SPEED CHANGE SYSTEM Filed Aug. 25, 1942- 6 Sheets-Sheet l HIS ATTORNEY April 2 1946- R. s. TAYLOR SPEED CHANGE SYSTEM.

Filed Aug. 25, 1942 6 Sheets-Sheet 2 INVENTOR R0 RT 5 774x402 BY Hi5 ATTORNEY April 1946. R. s. TAYLOR 2,398,814

SPEED CHANGE SYSTEM Filed Aug. 25, 1942- e Sheets-Sheet 4 INVENTOR HIS ATTORNEY ROB RTiTi R April 3, 1946. R. s. TAYLOR r 2,398,814

I SPEED CHANGE SYSTEM Filed Aug. 25, 1942 e Sheets-Sheet s '0 UIIIIIIIIIIIIIAYIIIIIA 7,,

INVENTOR ROBERT 5t 7J4YLOR HIS ATTORNEY Patented 'Apr. 23, 1946 UNITED STATES PATENT OFFICE 2,398,814 SPEED CHANGE SYSTEM Roberts. Taylor, Seattle, Wash. appl cants August 25, 1942, Serial No. 455,299

' 14 Claims. (01. 14-290) My invention relates to mechanism for changing speed ratios in vehicles; and more particularly to an auxiliary overdrive transmission for automobiles.

It is among the objects of my invention to provide an overdrive transmission embodying automatic means for changing between overdrive and direct drive in response to rotational and torque conditions in the unit, together with means associated with a control element, such as the throttie, for modifying the automatic operation to allow the unit to change back into overdrive at such times when eliminating the overdrive is desirable from the standpoint of engine performance.

Another object is to provide improved brake means for holdin a part of the gearing against rotation to. establish the overdrive ratio.

'Another object includes the provision of improved means for locking the unit in overdrive.

A further object is to provide an improved synchro-mesh clutch for connecting parts of the gearing together for direct drive.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forthin the following description of my invention. It is to be understood that I do not limit myself to this disclosure of species of my invention, as I may adopt variant embodiments thereof within the scope of the claims.

Referring to the drawings t Figure 1 is a side view, partly in section and partly in elevation, showing my auxiliary transmission interposed in the torque tube of an automobile, and showingportions f the clutch pedal and throttle mechanisms which enter into the control of my unit. r I

Figure 2, 3 and 4 are horizontal sectional views of the lock mechanism, taken in a plane indicated by line 2-2 of Figure 1. These views'areon considerably larger scale than Figure 1; and show the parts invarious operative positions.

Figure 5 is an axial sectional view of my transmission.

Figure 6 is a transverse sectional View, taken in a plane indicated by 1ine6-B of Figure 5, showing the overdrive brake and lock mechanism.

Figures 7 and 8 are transverse sectional views,

taken in a plane indicated-by line 1-1 of Figure 5, showing the overdrive brake and its operating mechanism; these views illustrating the parts in two different operative positions,

Figure 9 is a transverse sectional view, taken in a plane indicated by line 99 of Figure 5,showing the spring adjusting deviceforthe brake.-

Figure 10 is a detail sectional view showing the floating member of the .synchro-mesh clutch; and

Figure 11 is a transverse sectional view of the clutch shifting mechanism; taken in a planeindicatedby line Ill-I 0 of Figured. V

Figure 12 is a transverse sectional view, taken in a plane indicated by line I l l I of Figure 5, i1-

lustrating the one-way clutch.

Figure 13 is a fragmentary view taken in the direction of arrow l3 of Figure 5, showing portions of the floating clutch member and orbit gear connection. In this view the normally curved surfaces of the parts are flattened out into a plane to illustrate the structure more clearly.

Figures 14 to 1'7 are diagrammatic views showing the rotational and torque conditions in the planetary gearing at various stages of operation. In terms of broad inclusion, my speedchange transmission comprises a gearing embodying torque means for automatically changing between overdrive and direct drive; and means associated with the regular clutch and/or throttle mechanisms for'modifying automatic operation of the unit. The gearing employed in my transmission is preferably a planetary system; and the overdrive ratio is established by an improved brake and lock mechanism for holding apart of the screws 4. The housing is preferably interposed in torque tube 6 of an automobile behind the regular transmission 1, with sections of the tube engaged by necks 8 and 9 on the housing body and end plate respectively. Leading portion ll of'the propeller shaft provides the drive shaft of my --unit, and trailing portion l2 forms the driven shaft. 'When' power is being transmitted through the unit from drive shaft II to driven shaft I2 the mechanism is subjected to a cer-' tain kind of loading which'I shall refer to as a fdrivingloa'd; and when the rear wheels of the car tend to overrun the rate at which they are driven the mechanismis subjected to a. different loading which I term coasting load"; these terms being conventional in the trade.

.As shown in Figure 5, the overdrive transmission chosen for purposes of illustration comprises a planetary gearing having a planet pinion l3 journaled on shaft Hi mountedon a pinion ca rier l6 splined to drive shaft ll. Orbit gear I I of the planetary system is mounted for rotation with driven shaft l2 by a hub I8 splined to the shaft and provided with a flange I9 peripherally splined to the orbit gear and held by retaining ring 2 l. Sun gear 22 is formed as part of a sleeve 23 freely journaled on the drive shaft on a bearing 24.

The entire mechanism is journaled in the housinglby" two main bearings'26 rand'i2l. "Oneof these is disposed aboutthe drive shaftand'is-retained by end plate 3, while the other is interposed between hub l8 and neck 8 of the main housing. Hub l8 also carries speedometen. gear 28; and an oil retaining ring 29 is interposed between the hub and neck behind geari28.

Means are provided for holding thessun, gear against rotation to effect planetaiy operation of the system for establishing an overdrive-connection between theshafts. For thispurposea brake mechanism ..genera1ly;.indicated1 by reference numeral 3|, is employed; the brakeibeing enga ed by reverse..(counterrclockwise) torquev of the sun gear undercoasti-ng load,-.and'disengaged .by for-ward (clockwise) torque of the sun. ,gear

under driving load. InIthe present. specification the references to directionofrotationand'torque (clockwise and vcounter-clockwise)-.aretaken as viewed from the left in. Figure 5; the clockwise rotation being consideredas forward in the. consleeve 23-throughia shiftable wclutch member 34.

Hub-33 isfreely journaled -on ..drive shaft Hbby bearing 36 and is restrained. axially. by retaining ring. 31 and spacer bearings-38. -By this arrangement. the brake. rotor 32 is. connected -with..the

sun-gear wheneverclutch member 34 is intthe positionshown inF-igure 5 with: its-. tee.th-39 engaging teeth 4! and .42 respectively .of. thessleeve and: hub.

.Referring-to Figure 6, the overdrive brake fur-. ther com-prises a .-bar 43 .disposed transversely of and offset from. the rotor axis,-.-a-nd-ax-ial-ly slidable in-a. tubular: casing secured to. the-housingby' screws 46.

Brake -bar-43 has-a forward end 4! shape.d--to fit inpthe -iV.-shape.d notch formed between teeth 48,-onrrotor 32. ,In its'extended position the brake bar aengages the toothed rotor as-shown inaFigures. 6 and 7;and in its retracted-position the-bar isedisengaged from therotor as: illustrated in Figure 18. vIt-=is apparent thatthe-brake bar. is disengageableeby axial thrust appliedonitby rotor '32 when the latter-tends .to turn clockwise-under torque imposed by the-sun vgear when. the unit is subjected to driving load.

'Meansaretherefore providedforlocking the brake bar :against disengagement ;to .maintain theoverdrive -..connec.tion. -When 1' the brake is locked up, the sungear is thus held against. clockwise rotation, and the .drivingthrust:isstransmitted by driveshaft l Lto .orbit ;.gear ll through planet pinion 43 which in turnplanetates about the fixed sun gear. .The orbit.., gear. thusrotates forwardly at a faster rate,than.thedriveshaft, and this is reflectedby increased speed of driven shaft l2 in accordancewith-theusualplanetary overdrive principle.

As illustrated in. Figures ,2.,and-. 6,...thelocking means. comprises a plunger. .slidable within a ltransverseneckportion 52 of easing. vWhen the plunger is extended it lies between a pair of rollers 53 interposed between the end of brake bar 43 and a fixed reactor element or plug 54 threaded in the end of casing 44. In other words, when plunger 5| is inserted between the rollers, 5 the overdrive brake is locked against disengagement. The locking plunger is normally urged toward extended position by a spring 55 interposed between the plunger and a cap 51 threaded on neck 52.

Means associated with :the 1 throttle pedal 58 (Figure 1) is provided for-'retracting-lock plunger 5! to permit disengagement of the overdrive brake. A pull Wire 59 attached to the plunger is carried forward in a protective sheath 6| secured at its rear end to cap 51 by a clamp 62 .andterminating under the drivers compartment at a clamp.63. The forwardly projecting end of wire-59 carries a stop 64 engageable by an arm fifitonthe throttle rod 61. Stop 64 is normally spaced ahead of arm 66 so wire 59 is pulled to start retraction'of plunger 5| at the end of the throttle stroke when; pedal 58- is' fully depressed. Rollers 53-permit 'the'plunger to be pulled out easily against the axial thrust imposed on brake bar 43 by the sun-gear torque. The normal operation 'of' the throttle 'pedal'is'not interfered with as the plunger need-beretracted by the throttle onlyjust enough to allow a' roller 53 to move under the inclined face of "the plunger, whereupon the axial thrust of bar 43 lifts'the plunger to the partially retracted position shown in Figure 4. With the brake thus disengaged, the unit is free to go into direct drive.

Means are alsoqpreferablyprovided to unlock thebrake to permit disengagement thereof-when the regular clutch pedal H is :depressed to slow up the-car or shift gears. Another stop'BB is preferably arranged on wire 59 to be engaged by a suitable linkage 69 connected to the clutch'pedal H so that plunger 5| of my unit is fully retracted 'when'theclutch'pedal is depressed. 'Means'are also provided for latching plunger5l in the fully retracted position. As'seen-in Figure -'3, a-latch plate 12 is pressed forwardly under a shoulder '0f the plunger by a-spring'13, thus holding the plunger retracted even 'thoughthe clutch pedal has movedback. The brake bar 43 is now free to retract whenever a clockwise'torque is put on the brake rotor by'the sun-gear, so that the unit so can go into direct drive.

Upon-retraction of brake bar'43 it kicks over "a pivoted finger l4-to-disengage latch plate 72 'and allow spring pressed plunger 5l' to 'rest on i one ofrollers 53 as shown in Figure 4. The

plunger with its tapered nose "I6 is now ready for reinsertion between the rollers whenever the brake" bar is again extended.

Means are provided for extending bar 43 to 'reengage brake rotor 32 when-thelatter turns "counter-clockwise'underreverse' torque of the sun gear occasioned" by acoasting load.on theunit.

"As illustrated in'Figures' 5, '7 and 8, an annular plate H is connected for counter-clockwise turn- 05 ing'with rotor.32"byspring presse'dv ratchets 18 mountedon the innerperiphery ofthe plate and engaging ratchet teethil9.forme d on aring 8| splined to rotor hub. 33. Retainer rings -82 securedon opposite sidesofplate H .by bolts 83 serve to holdtheparts together.

Plate 11 is in turn-connected to brake; bar 43 by.a.1ink 84. This link. 1ies between the plate and rotor as seen inlFigure5, andpreferably comprisesa rod having outturned ends 86and 81 to form pivotal engagements with the plate and f In the preferred construction a tangent spring 9I is interposed between brake actuating plate I1 and an anchor plate 92 mounted onendpl'ate 3'of thehousing. This spring has outturnedfends I 93 and 94 for engaging plates 11 and 92respectively. In the brake engaged position of the parts as shown in Figure '7 the tangent spring exerts a force of about 33 lbs. clockwise onplate 'II;"and in the brake disengaged position. the spring force is about 30 lbs. clockwise.

. Opposing this force is a spring'presse'd toggle device comprising a slidable arm 96 pivotallyconnected to plate II by a short link 91, so that the link moves between the collapsed position of Figure 7 and the extendedposition of Figure -8'.. A.

guide arm 98 is connectedbetween thehousing and elbow pin 99 of the toggle; there being sufficient play at the joint to allow for the straight line motion of arm 96. Figure shows that arm 5H5 is tubular in form to receive spring IflIwhich is interposed between the arm and a thimble I02 ;in which the arm is slidably mounted. In the brake engaged position, spring Il'II acting on the full lever arm of link 91 exerts a force of about 36 lbs. counter-clockwise, thus providinga resultant counter-clockwise force of about 3 lbs. tending to hold the brake bar engaged.

In the disengaged position shown in Figure 8 the extended link 9'! is about 1 /5 degrees over center, imparting a force of about 1 lbs. clockwise and acting with tangent spring 9| taproduce a resultant of about '31 /2 lbs. clockwise tending to hold the brake ba'r'disengaged. Thus,

at the beginning of the brake engaging operatiori, a counter-clockwiseturn of less than 2 degrees throws the toggle link over center, and

thereafter the toggle device acts with increasing force against the tangent spring (thus reducing the applied effort required to engage the brake) until finally the tangent spring force is overcome by the toggle mechanism. This arrangement insures that any torque suflicient to start the brake engaging movement is enough to complete it Means are provided for adjusting the tension of tangent spring 9I. Referring to Figure 9, a pair of adjusting screws I03 are provided on end plate 3 of the housing to engage ears I04 on the periphery of anchor plate 92. These parts are soarranged that by alternately turning up and backing off the screws the anchor platemay be turned any required amount, depending upon the spring tension desired.

From the preceding description of the brake mechanism it is apparent that-with the brake unlocked it will disengage to release the sun. gear under the torque conditions imposed by a driving load. In order to establish a direct driveeonnection upon release of the sun' gear, means are provided for lockingthe parts of the planetarythe inertia of brake rotor. 32 and the connected tween an inner clutch ring I01 formed on sungear sleeve 23, and anouter clutch ring I08 having a flange I09 peripherally splined to an end of the orbit gear and held by retaining ring III.

The clutch rollers are held by a, suitable spring pressed cage II 2, and coact with flats on the inner clutch ring I 01 to connect the sun and orbit gears together when the sun gear tends to run clockwise at a rate faster than the orbit gear. I

The one-way clutch thus functions to lockup the planetary gearing as soon as the sun gear is released byfoverdrivefbrake 3|, because a driving load onthe unittends to spin the sun gear clockwiseh Shock of clutch engagement is avoided by parts which function as a flywheel to prevent the released sun' gear from accelerating too rapidly. With this inertia load to overcome, the

sung'ear graduallycomes up to the speed of the orbit gear, whereupon the one-way clutch engages smoothly and without clash. I

"Means arestilifurther provided for shifting the slidable clutch member 34 to positivelylock the parts of the planetary gearing together for direct drive. ,When member 34 is in the left hand position shown in Figure 5, the sun gear is connected with the overdrive brake as has already been described. Byshifting the member toward the right the brake'mechanism is cut out and positive connection is established between the sun and orbit gears. Shifting is accomplished by a. yoke H3 engaging an annular groove H4 in member 134. The yoke is splinecl to a shaft H5 I journaled in the'housing A spring H6, Figure '11, interposed between the shaft and housing normally urges clutch member -34 toward the Referringnow to Figure 1} the external part of the yoke shifting means comprises a lever Hl secured to shaft H5. Asecond lever H8 is pivoted to the housing i on a pin II9,}and is connected tolever' II! by the link I22; pivoted to 'lever H8 bythe in-12L In the positionof'the linkage shown in Figure .1, clutch member 34 is* toward the left as illus- "trated in Figure 5,.thus renderingthe overdrive brake effective. Butwhen the lower end of lever 1 H8is pulled forward or the lower end-of lever II'I'is pushed back,"clutch member 34 is shifted to the right to cut out the overdrive brake and establish: the "direct drive connection. During this operationof the linkage, link I22 swings down over the center of pivot I I9 until a lip I23 on the link. engages an'edge of lever H8, thus locking clutch member 34 right hand position. The parts will be held in the direct drive position until lever "I I8 is swung back to move link I22 over center and allow spring I I6 to shift clutch member 34 forward again. A U-shaped spring I24, interposed between pin I2I, and pin j I25 on the housing is compressed as link I22 passes over its center position, and functions to snap the linkage fromone position to the other. A slidablerodqIZfibearingfagainst leverflIITI is connectedgat' its forwardend to an arm, I2'I fixed to a projecting part I 28 of the reverse shiftin bar in regular transmissionl By this arrangement, my unit is shifted into direct drivewhem ever the regular transmission is put in reverse "gear? Since the direct drive connection established by clutch member-M is a positive one, the reverse-torque is readily transmitted through the i I. i L 1.. L,

A control wire 12! isconnect edwith lever I I8 .asuitable operating button I32 on the dashboard 1 Hi3. By pulling this wire the unit may bemanand orbit gear part I 08.

ually shifted into direct driveat anytime. Furthermore, pushing on the wire I29serves to swing lever H3 back to move link I22 over center and thereby reestablish the overdrive brake connection. This latter manipulation also allows the driver'to reestablish connection with the overdrive brake after the unit has been put in direct drive-by a reverse shift of the regular. transmission. r

The means for positively connecting the sun and orbit gears together when clutch member 34 is shifted to the rightincludes a synchro-mesh feature. As shown in Figure 5, a floating clutch ring ltd is-interposed between sun gear sleeve 23 This floating ring. is freely journaled on the sun gear sleeve and is connected for limited turning movement relative .to part Hi8 by end teeth I36 .on ring I34 loosely meshed with teeth I31 on part I08 respectively. Figure 13 clearly shows the free play between these teeth which allows for the desired relative movement.

Floating ring I34 also has peripheral teeth I38 adapted to be engaged by the internal teeth 39 on clutch member 34 when the latter is shifted insure meshing of the-teeth in most positions of the sun and orbit gears. The adjacent ends of teeth 39 and 138 are also beveled as indicated by V bevels I39 on teeth I38. in Figures 10 and 13.

Should the teeth meet. end on, these bevels usually will force thefioating ring to turn enough to permit meshing; it being remembered that the floating ring is free to turn a limited degree relative to the shiftable member because of the loose connection with partIilB. 7

The only other condition to take care of is the exceptional one where the narrow flat end faces of teeth 39 and I38 happenv to abut squarely. Therefore I provide inclined .planes I M at the bases of teeth I31 onpart I08, adapted to turn floating ring I34 upon axial pressure applied to the floating ring by shiftable member 34. See Figure 13. This turning is enough to move the flat ends of the teeth out of abutment and permit meshing thereof.

Lubrication of my unit is preferably by means of oil retained in the lower portion of the housing. oiling of the confined parts of the planetary gearing is insured by a helical impeller or screw I42 disposed between the periphery of part I 08 and a hollow casing I63. This pump picks up oil from the housing and delivers it under pressure to the planetary gearing through an opening Hit in flange N39. The .oil is. then discharged back into the housing through an opening I46 inflange I9. Part of the oil is fed under further pressure to the planet pinion bearing I41 by a scoop ring I48 secured to the planet pinion carrier l5 and having a raised lip portion adjacent the pinion shaft to provide an opening I49 for scooping the oil-and directing it into longitudinal passage I5I of the pinion shaft. A transverse passage I52 in the shaft leads to the pinion bearing. 7

Operation.--With the structure hereinbefore described in mind, and with particular reference to Figures 70 to 1'7, the operation of my unit is as follows: Consider that the shiftable clutch member 34 is positioned as in Figure 5 to render the overdrive brake active, and also consider that the 7 brake is engaged as in Figure 6 with locking plunger 5| inserted as inFigure 2. lThe unit is now locked up in overdrive, and the directions of rotation and torque inthe planetary system are illustrated in Figure 14. Under driving load the .torque on the sun gear is forward and this thrust is taken by locked brake bar 43. Pinion I3 planetates about the fixed sun gear and drives orbit gear I! forward at a faster rate than the driveshaft, producing the overdrive ratio. At this time the direct drive clutch I65 is disengaged because. the orbit is overrunning the sun gear clockwise.

Let us suppose now that the driver fully depresses the throttle pedal 58 or depresses clutch pedal II. In either case locking plunger 5| is withdrawn, and if withdrawn by the clutch pedal it is latched out by plate I2. Forward torque of sun gear 22 under driving load as shown in Figure 15 then retracts bar can; disengage the brake .and release the sun gear. One-way clutch I05 immediately locks the sun and orbit gears together so that the gearing rotates as a unit to produce the direct. drive' ratio. If the lock plunger 5I was'latched out, retraction of brake bar 43 unlatches the plunger, and the latter seats on a roller .53 ready for reinsertion between the rollers when the brake bar is again extended. In the direct drive connection as'illustrated in Figure 16, the sun gear rotates forwardly (clockwise) along with the other gears. Brake rotor ,32 also runs forward, which it is free to do because'brake bar .43 is held disengaged by tangent spring 9|. Ratchets 13 are of course disposed to allow free clockwise rotation of the brake rotor.

The unit remains in direct drive as long as there is a driving load on the unit. However, when the momentum of the car puts .a coasting load on the unit, orbit gear I! tends to rotate clockwise faster .than the rate at which it is driven from the engine. This causes planet pinion I3 to start turning clockwise about its own axis, causing a reversal of torque on the sun gear and tending to turn the latter and the connected brake rotorbackwards (counter-clockwise). as illustrated in Figure 17. As a result, plate TI is turned backward through ratchets I8, thus pulling brake bar 43 into engagement with the toothed rotor. When the sun gear is stopped by the brake, pinion I3 is forced to planetate about it and reestablish the overdrive connection between the shafts. Immediately upon extension of brake bar 43, plunger 5| reinserts itself between rollers 53 to relock the brake against disengagement.

In the operation of my improved overdrive transmission it will be noted that the torque operated brake for holding the sun gear is under the control of the driver by reason of the connections with the regular throttle and clutch mechanisms, whereby the unit changes back into direct drive at such times when eliminating the higher gear ratio is desirable from the standpoint of engine performance. Thus, when greater acceleration is desired topass another vehicle, or greater power is required to make a grade, the driver needs onlyto depress the throttle pedal fully to cut out the overdrive. My mechanism also insures adequate starting torque in any of the forward gear ratios of the regular transmission because the overdrive is cut out whenever the regular clutch pedal is depressed in starting the car or shifting gears.

The mechanism also enables a. reverse torque to be transmitted through my unit for backing the car, because the planetary gearing is positively locked together for direct drive whenever the regular transmission is shifted into reverse. Furthermore, the driver can cut out the overdrive at any time he desires by pulling the dash control button I32.

Another feature in the operation of my mechanism is that the unit function as a hill-holder in overdrive. Should the car start rolling backwards the one-way clutch I will engage and put a counter-clockwise torque on the sun gear and connected brake rotor 32. As seen in Figure 5, brake bar 43 prevents rotor 32 from turning counter-clockwise because the thrust is taken transversely across the bar to the housing or fixed element. The sun gear being thus blocked, the rear wheels are positively locked against reverse rotation and backward rolling is prevented.

I claim:

1. In a speed change system, a gearing, a rotor, means for selectively connecting or disconnectin the rotor with the gearing, and a bar positively engageable with the rotor to hold a part of the gearing against rotation and movable along an axis spaced from and transverse to the axis of the rotor.

2. In a speed change system, a gearing, a rotor, means for selectively connecting or disconnecting the rotor with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, and means for mounting the bar to disengage under thrust of the rotor for releasing said part.

3. In a speed change system, a gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the bar to disengage under thrust of the rotor for releasing said part, and means for locking the bar against disengagement.

4. In a speed change system, a gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the bar to disengage under thrust of the rotor for releasing said part, means for locking the bar against disengagement, and means for controlling the locking means.

5. In a speed change system, a gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the bar to disengage under thrust of the rotor for releasing said part, a plunger for locking the bar against disengagement, and means for retracting the plunger to unlock the bar.

6. In a speed change system, a, gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the bar to disengage under thrust of the rotor for releasing said part, a plunger for locking the bar against disengagement, means for retracting the plunger to unlock the bar, and means for latching the plunger in retracted position.

'7. In a speed change system, a gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the bar to disengage under thrust of the rotor for releasing said part, a fixed element, a pair of rollers interposed between the bar and fixed element, and a plunger insertable between the rollers for locking the bar against disengagement.

8. In a speed change system, a gearing, a rotor connected with the gearing, an elongated rod positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the rod, so as to be movable alon its axis and to disengage under thrust of the rotor for releasing said part when the rotor turns in one direction, and means responsive to turning of the rotor in the opposite direction for engaging the rod with the rotor.

9. In a speed change system, a gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, a turnable plate, a link connecting the bar and plate, and means connecting the plate and rotor to engage the bar with the rotor upon turning of the rotor.

10. In a speed change system, a gearing, a rotor connected with the gearing, a bar positively engageable with the rotor to hold a part of the gearing against rotation, means for mounting the bar to disengage under thrust of the rotor for releasing said part when the rotor turns in one direction, and means responsive to turning of the rotor in the opposite direction for engaging the bar with the rotor, and resilient means for urging the bar into either one or another of its operative positions.

11. In a speed change system, a planetary gearing including a sun gear, a rotor connected with the sun gear, a movable bar positively engageable' with the rotor to hold the sun gear against rotation, means for mounting the bar to disengage under thrust of said rotor for releasing the sun gear, and means including a one-way clutch for locking parts of the planetary gearing together for rotation as a unit upon release of the sun gear.

12. In a speed change system, a planetary gearing including a sun gear, a rotor connected with the sun gear, a movable bar positively engageable with the rotor to hold the sun gear against rotation, means for mounting the bar to disenga e under thrust of said rotor for releasing the sun gear, and means including a one-way clutch for locking parts of the planetary gearing together for rotation as a unit upon release of the sun gear, said rotor having sufficient inertia to retard acceleration of the sun gear after its release so that the clutch engages without shock.

13. In aspeed change system, gearing including sun and orbit gears, a rotor, a bar positively engageable with the rotor to hold the rotor against rotation, means for mounting the bar to disengage under thrust of the rotor, and means for selectively connecting the rotor to the sun gear or the sun gear to the orbit gear.

14. In a speed change system, gearing including sun and orbit gears, a rotor, a, bar positively engageable with the rotor to hold the rotor against rotation, means for mounting the bar to disengage under thrust of the rotor, a plunger for locking the bar against disengagement, means for retracting the plunger to unlock the bar, and means for selectively connecting the rotor to the sun gear or the sun gear to the orbit gear.

RQBERT S. TAYLOR. 

